What is this antenna clamp called?

[DirtFarmer]

Hello, this is my first post here. My old tabletop radios have these antenna clamps attached to the power cord, but I just picked up a nice Silvertone that does not have this clamp.

What is the proper term for them, and where can I buy them? Or can I pry one off of another radio? Or can I use something instead of this?

Thanks in advance from a noob!